Scientists Optimize Wall-Less Hall Thruster For Deep Space Missions

Scientists from the French National Center for Scientific Research have succeeded at optimizing the longevity of wall-less hall thrusters for future deep space missions, and the latest innovation is a big improvement on the conventional hall thruster used in former times.

Hall thrusters according to the scientists are advanced electric rocket engines designed to keep station and control geosynchronous communication satellites and space probes. These rocket engines consume 100 million times less energy or fuel than normal rockets, and could be used to explore asteroids, Mars, and the outer rim of the solar system.

Its fuel efficiency makes it good for ferrying larger cargo for space missions, while also leaving enough space for spacecraft among other things. The only problem for now is that while most space exploration missions require a minimum of 50,000 operation hours, hall thrusters for now has only 10,000.

Publishing their findings in the journal Applied Physics Letters of the American Institute of Physics, the scientists made this latest hall thruster from the prototype they developed nearly a year ago. At a speed of 45,000 mph, hall thrusters propel spacecrafts forward to attain deep space missions in no time. It uses xenon as fuel or propellant gas, and this is ionized by electrons caught up in its magnetic field.

"The major drawback of Hall thrusters is that the discharge channel wall materials largely determine the discharge properties, and consequently, the performance level and the operational time," said Julien Vaudolon, the primary researcher in the Electric Propulsion team led by Professor Stéphane Mazouffre in the ICARE-CNRS Laboratory, France.

According to Vaudolon, the material wall helps the properties of the plasma by a secondary electron emission where high energy ions hit the channel wall surface in order to create the emission of secondary electrons. But the erosion of the discharge cavity causes the high energy ions to reduce the lifespan of the hall thruster.

"Thus, an effective approach to avoid the interaction between the plasma and the discharge channel wall is to move the ionization and acceleration regions outside the cavity, which is an unconventional design named a Wall-Less Hall Thruster," Vaudolon said.

All said and done, the research team is not resting yet; they have studied certain mechanics by testing the PPS-Flex version of the hall thruster, and now getting set to design a more functional and promising hall thruster that is based on wall-less architecture.